Law enforcement personnel stand at a roadblock along just south of Doyline, La. on Saturday. Authorities have begun moving 1 million pounds of improperly stored explosive powder to storage bunkers at the Camp Minden industrial site.

DOYLINE, La. — Weather could complicate the transfer of roughly 6 million pounds of explosives that were haphazardly stored at an industrial site in northwestern Louisiana and led to the evacuation of a small town, a state police spokeswoman said Monday.

If lightning is spotted within five miles of the site, authorities will suspend efforts that began on Saturday to move the artillery propellant, Lt. Julie Lewis said.

Light rain fell at midday in the vicinity of the site near the town of Doyline. No lightning was expected Monday, but thunderstorms were forecast for today.

Officials estimate that more than half of Doyline’s 800 residents heeded police advice to evacuate in advance of the cleanup at the Explo Systems Inc. site. Col. Mike Edmondson, commander of Louisiana State Police, said the material is stable and would need an ignition source to explode. The precautions were taken because officials fear that any spark could set off a huge explosion of the material, which they said was stored improperly in a relatively small area.

One of several residents who relocated to a nearby state park expressed exasperation at the sheer volume of explosive material, which is more than authorities initially estimated.

“We got outside the evacuation area when they said there was a million pounds. Now it’s six million,” said Frank Peetz, 71, who was staying with his wife in a camper. “Maybe we ought to be up in Arkansas somewhere.”

Edmondson was hesitant to estimate when it would be safe for Doyline residents to return home. He also said state police weren’t sure how much damage an explosion of the material could cause, even after consulting with Department of Defense officials.

“Nobody can tell you what 6 million pounds of explosives would do if it went up,” Edmondson said in a telephone interview. “And I don’t want to find out.”

Edmonson said that Explo Systems leases and controls about 400 acres of the 15,000-acre Camp Minden, a former ammunition plant that now is a state-owned industrial site and home to a National Guard training facility. He estimated that the M6 propellant was stored in an area of less than 10 acres.

It was discovered there, stored indoors and outdoors, sometimes in containers that had spilled open, by a trooper following up on an October explosion at the facility.

Explo is now the subject of a criminal investigation, state police said.

The company has not publicly commented on the investigation. Its website says the company has been in existence for seven years and that its management has been “demilitarizing” and recovering explosives and propellant for 15 years.

Authorities had initially estimated the total of M6 stored at the site at 1 million pounds after the first investigator saw cardboard boxes on long rows of pallets behind a building. Police found more stacked in sheds and warehouses when crews returned Saturday to begin moving the boxes into bunkers about two miles away on the former munitions site, state police spokesman Capt. Doug Cain said Sunday.

“It wasn’t in their storage magazines. They had it hidden on the property, away from the storage magazines where we would expect to find it,” Cain said.

Edmonson said “it was stuffed in corners. It was stacked all over.”

He said that in two days, crews had moved nearly a million pounds from the tightest-packed buildings into approved containers and onto 27 tractor-trailers to move to storage bunkers. Another 250,000 pounds had been moved a safe distance from the bulk of the material. It won’t all have to be moved into bunkers to let people return home — the evacuation could be lifted once the propellant is divided into amounts that won’t threaten the town if some ignites, with each area a safe distance from the others, Edmonson said.

Company officials could not be reached Sunday. The owners were believed to be returning Monday from a business trip to South Korea, but a manager has been working with state police from the start, Edmonson said.

A call to a Shreveport attorney who represents the company was not returned Monday.

Doyline was used to film some scenes for the HBO vampire series “True Blood.”